The closest analogue of the claimed technical solution is a piezoelectric pump to displace fluid, the pump is part of the dispenser described in the U.S. Pat. No. 7,682,354, 23 Mar. 2010, U.S. Class 604/890.1. The pump includes a housing, a rear piezoelectric clamp section, a piezoelectric extender section, a front piezoelectric clamp section, the sections are contained in the housing and connected in series. The clamp sections are mace of piezoelectric material that can press on the walls of the housing from inside at accession of an electric potential to them. The piezoelectric extender section is made of a material capable to change its length at accessing of an electric potential to it.
The main drawback of the analogue is that the displaced fluid contacts friction surfaces of the housing and the clamp sections, because the front clamp section acts as the fluid displacer in this design. It cause low clamping force and as a consequence cause low pump pressure. Also it may cause corrosion, wear and quick pump failure when chemically aggressive fluid, or fluid with smallest hard particles contact friction surfaces of piezoelectric housing and clamp sections. Existence of gaps between the ends of clamp sections and the housing in the phase where an electric potential is not accessing to them may be considered as disadvantage. This cause vibration during operation, low reliability and low efficiency.